Muddy flows and floods in Limburg, the Netherlands: impact and response

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2 Muddy flows and floods in Limburg, the Netherlands: impact and response Presentation: Harrie Winteraeken COST634 small working group Louvain la Neuve, 4 december

3 Contents presentation Overview of the problems in our region Measures and Solutions until now For the future: effective measures and sustainable land use? 3

4 Water Board Roer and Overmaas Flat area: agricultural, desiccation water level control Hilly area: urban, flooding soil erosion! 4

5 Water management in relation to flooding and erosion National Agreement on Water: higher protection levels for urban areas (reserving, storing, draining) Climatic change: heavier rainfall Water Board R&O: at 500 l/s responsibility Municipalities & Farmers: small scale problems 5

6 Parties involved Province: coordinates, facilitates and sets out main policy Waterboard: managing surface waters Municipalities: sewer system, local problems Limburg Agri- and Horticulture Alliance: interests of farmers Land reconstruction projects and Office of Land reform 6

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8 Catsop - Beek, 8 May

9 Catsop - Beek, 8 May

10 Catsop - Beek, 8 May

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15 Crapoel, Winter

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19 Erosion policy and instruments Rain water buffers and grassed waterways Erosion covenant Permanent grassland agreement Erosion ordinance Farmers erosion management plan 19 Leuven: research no-turning-tillage

20 Rain water basins About 275 rain water basins are constructed About 50 basins are in planning 20

21 Water basins: Good protection of villages from mud and water But: End-of-pipe! Sedimentation of mud (maintenance) Overflow still contains a lot of sediment Erosion in the catchment still takes place 21

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24 Gerendal, 30 April

25 Regenwaterbuffer Catsop 25

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29 29 Etzenradergrub

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32 32 Field level: source measures

33 No-turning-tillage / mulch 33

34 Effectiveness mulch / NTT Results research INTERREG 3 by K.U. Leuven: Average 40 % less runoff Average 54 less erosion (simulations) Average estimation 88 % less erosion on surveyed fields And also: 43 % less runoff of nutrients. 34

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36 Erosion: mulching & green strips Resultaten sedimentverlies bij verschillende Results sediment lost at a parcels with different erosieremmende lengths and maatregelen, widths of T=25 green en helling=10% strips Sed 400 (kg) sed(kg) 200 mulch Mulch groenstrook Green strip groenstroken200m Green strips every 200 m groenstroken300m Green strips every 300 m mulch+groenstrook Mulch + green strips mulch+groenstroken200m Mulch + green strips every 200 m mulch+groenstroken300m Mulch + green strips every 300 m Parcel hellinglengte length (m) 36 * Results are based on LISEM calculations

37 Erosion Ordinance (general measures) Soil tillage in autumn after harvest Fields with average slope > 18% must be grassland Soil covering in wintertime (mustard / rye) Grass strip / ditch down slope parcel 37

38 Erosion Ordinance (specific measures) Cultivation of sugar beats, potatoes and corn > 2 % slope Maximum length parcels 400 m (2-5%) 300 m (> 5 %) Mulching, no tillage, straw cover (corn / wheat) 38

39 Farmers Erosion Plan Individual plan in which a farmer can choose from different erosion prevention measures Gives dispensation of main rules of the Erosion Ordinance Measures are given points on the basis of effectiveness and acceptance by the farmers Obligatory score 40 points per hectare 39

40 Some measures FEMP s Winter wheat (crop rotation) 16 % Green manure 18 % Contour ploughing 15 % No turning tillage 15 % Green manure & nt-tillage 9 % Greenbelt 6 % Grassed waterway 0 % Rain water basin 1 % Other measures 20 % Total amount of measures: % 40

41 Evaluation FEMP: runoff waterafstroming bij BEP en EVO (niets doen is 100 %) % alle percelen kritische percelen kritische percelen 41 Niets doen Bedrijfserosieplan Erosieverordening verschil EVO-BEP alle percelen

42 Evaluation FEMP: erosion Erosie BEP en EVO (niets doen is 100 %) % alle percelen kritische percelen kritische percelen 42 Niets doen Bedrijfserosieplan Erosieverordening verschil EVO-BEP alle percelen

43 Evaluation FEMP s: first conclusions Erosion Ordinance is more effective than FEMP FEMP costs lot of administrative work for farmers Water Board has to check FEP s Province has to check measures in the field: difficult End of the FEMP? 43

44 Permanent Grassland Agreement with farmer not to plough grassland into arable land. Ransom (once payment) of ± / ha Where? Grassland on slopes > 5 %, in stream ways and valley bottoms upslope urban areas / also grass strips Who? Water Board & Province : 60 ha ( ) Land reconstruction: 5 for 4 ha in cooperation with promotion dairy cattle & manure policy 44

45 The Strategy: NTT / mulch!? More and heavier rainfall / climatic change National Agreement on Water: higher level of protection urban areas Water system needs more capacity NTT / mulch: more infiltration into the soil NTT / mulch:substantial reduction of run off Water system needs less more capacity 45

46 New Strategy: the differences Protection / return period & climatic change Erosie in werkgebied Elkenrade, Ransdalerveld sed (ton) T=10 nieuw T=25 T=10 +10% T=25 nieuw T=25 +10% mulch/niet-kerend Mulch/ no turning tillage lijnvormige elementen Green strips huidig landgebruik Worst case situation * Results are based on LISEM calculations 46

47 Costs and benefits Water Board: more capacity of the water system / rain water buffers Investments in South Limburg: Present land use: ± 39 million With NTT / Mulch as common practice: ± 10 million 47

48 Recent research Costs and benefits NTT INTERREG 3 by the Farmers organisation Boerenbond Consult and Research Farm Wijnandsrade Average harvest equal or slightly more Protection crops against plagues? New research Herbicides: more Glyfosaat (Round Up)? New / heavy machinery? Total costs 0 60 / ha (av. 48 / ha) Farmers: It is not to much asked! 48

49 Other benefits Mulch / NTT Long term: sustainable land use and economic value of the land Ecological: less pollution of surface waters & sufficient impact on EU Framework Directory Water? Social: less damage image farmers because of less nuisance civilians Farmers should take their responsibility 49

50 How to introduce Mulch / NTT? Water Board: to guarantee the protection level of the water system, we must can rely on mulch / NTT! Only little exceptions necessary? Farmers want to make their own choice The stick or the carrot? 50